Bristlenose Pleco

Ancistrus is the most aquarium-suitable of the suckermouth catfish sold in shops as "algae eaters." Males have soft, branch-like growths (bristles) on the snout. Besides the normal form, brown with light spots, there are also albino, "super red" and long-finned types.

Important warning: Pterygoplichthys and Hypostomus species, also sold as "algae eaters," reach 40–50 cm and do not fit in normal aquariums. Ancistrus, on the other hand, stays around 12 cm.

It lives on rocks, fallen trees and roots in fast- and moderately flowing, oxygen-rich rivers and streams of the Amazon basin.

• Volume: 80 liters for one individual; a larger footprint for more than one male.
• Driftwood is essential: Ancistrus rasps on wood; this fiber is necessary for its digestion.
• Hiding places: Caves, tubes or spaces under roots. Males claim a cave of their own.
• Water: Clean, oxygenated, with gentle flow.

It is mainly herbivorous, but not entirely:

• Sinking spirulina/algae wafers
• Blanched zucchini, cucumber, peas, spinach
• Frozen bloodworms or shrimp once a week

The algae in the aquarium alone is not enough. Since it is active at night, feeding after the lights go off gives good results.

Peaceful; it leaves other fish alone. Males fight each other over caves; more than one male requires more than one cave. It is rarely seen sucking the slime coat of slow, flat-bodied fish (discus, angelfish); plenty of food prevents this.

Good companions: Almost all community fish, angelfish, discus, shrimp.

Avoid: Goldfish (temperature does not match), large cichlids that claim the bottom.

Ancistrus is not a schooling fish; it lives happily on its own. If more than one is kept, the number of males should be limited: males fight over caves and territory. Each male needs a separate cave and hiding places in different parts of the aquarium.

Those who want to breed them start with 1 male and 1–2 females; the females visit the male's cave in turn. Two males are not recommended in an aquarium under 100 liters.

It is one of the easiest suckermouth catfish to breed in the aquarium. The male cleans his cave, the female lays a cluster of orange eggs there, and the male guards the eggs, fanning them until the fry are free-swimming (4–10 days). The fry immediately start eating vegetables and wafers.

Hardy. Nitrate buildup and lack of oxygen cause problems. A sunken belly is a sign of starvation. It is sensitive to many medications, especially copper.

Mature males have prominent branch-like growths on the snout and around the head. Females lack these growths or have only a short row along the edge of the mouth.